Research Of Maize Somatic Embryogenesis-related Gene ZmSERK

Maize (Zea mays L.)，as the country’s largest food crops, its yield changes willdirectly affect the development of China’s agricultural economy. As we all know, inmaize transgenic breeding, its receptor system’s setting plays a key role. Practice hasproved that obtained embryogenic callus of maize immature has a strong long-termsubculture capacity and ability to regenerate, and thus become the ideal receptormaterial., But,Research found that maize is one of the most difficult crops of in vitroembryogenesis. Therefore, to understanding the molecular mechanism of maizeembryonic callus formation, Controlling somatic embryogenesis gene cloned frommaize callus,is an important part of corn transgenic breeding. It has a very importantsignificance for the genetic engineering of improved varieties to improve theregeneration of transformants.In the experiment， the embryogenic calli (EC) of maize inbred lines Y423wereused as materials for cloning SERK；and then the dynamical changes of the mRNAtranscription levels of this gene was further determined by real-time reversetranscription PCR during maize somatic embryogenesis,which lay the foundation forthe better understanding the regulatory mechanism of SERK and some other somaticembryogenesis-related genes during maize somatic embryogenesis. The main resultswere as follows:In this study, we cloned the somatic embryogenesis-related gene ZmSERK frommaize using RT-PCR.The sequencing results showed that the nucleotide sequencecontained a complete open reading frame,its full length was1881bp,It encoded aprotein of a627amino acid with a predicted molecular weight of a69-kDa and a pI of5.55. Bioinformatics analysis of this Amino acid sequence showed it shared above80%identities to Poa pratensis, Oryza sativa L.. It confirmed that we had cloned theSomatic embryogenesis receptor-like kinase SERK gene in maize.The gene was firstlycloned from major corn inbred lines of Northeast, therefore we submitted it into NCBIGenBank database,the number is KJ004522. And then we predicted the structure and biological properties of the proteinusing bioinformatics software.In this study expression differences in transcription level of ZmSERK from theinduction and differentiation process of Maize were analyzed by Real-time qRT-PCR.The results demonstrated that it was expressed difference in the induction anddifferentiation process the relative expression level of14th day was the highest of all.In this study, the plant expression vector pCAMBIA3301-ZmSERK andihp-RNAi expression vector p3301-UBI-SERK(+)-intron-SERK(-) was successfullyconstructed, and was transferred into somatic embryogenesis induced by maize inbredlines Y423, by Agrobacterium tumefaciens-mediated. then the somatic embryogenesis were selected on the medium containing the concentration of bialaphos for2mg L-1. The transgenic plants were confirmed by PCR and PCR-Southern analyzedby Real-time PCR. Based on the result of real-time reverse transcription PCR,itshows that expression of ZmSERK in the transgenic plants with ihp-RNAi expressionvector lower compared with the wildtype and the transgenic plants which wastransferred into expression vector expression level increased slightly compared to thewild-type.